Asahi Takumar 500mm F/4.5

Super telephoto prime lens • Film era • Discontinued

Model history

Asahi Tele-photo Takumar 500mm F/5M2 - 111.00m-- 1953 
Asahi Takumar 500mm F/5 [326, 43260]M2 - 111.00m-- 1957 
Asahi Takumar 500mm F/4.5 [366, 43660]M4 - 410.00m-- 1966 
Asahi Super-Multi-Coated Takumar 500mm F/4.5 [43661]M4 - 410.00m-- 1971 
smc Pentax 500mm F/4.5M4 - 410.00m-- 1975 

Specification

MF
Manual
Built-in hood

Optical design:
500mm
F/4.5
35mm full frame
M42 [45.5mm]
(35mm full frame)
4 elements in 4 groups
Diaphragm mechanism:
Diaphragm type:
Manual
Aperture control:
Aperture ring
<No data>
Focusing:
10m
<No data>
Focusing modes:
Manual focus only
Manual focus control:
Focusing ring
Physical characteristics:
3500g
⌀126.8×440mm
Accessories:
Removable front filters are not accepted
Rear screw-type 49mm
Built-in telescopic round
Not available

Sources of data

  • The Ultimate Asahi Pentax Screw Mount Guide 1952-1977 book by Gerjan van Oosten (1999).
  • Lenses for the Honeywell Pentax booklet (October, 1965).
  • Asahi Pentax Takumar interchangeable lenses operating manual (PUB. 06081).
  • Honeywell Photographic Products booklet (March 1969).
  • Honeywell Pentax cameras, lenses, and accessories booklet (March 1971).
  • Honeywell Photographic GSA Catalog and Price List (December 1, 1970 through November 30, 1971).
  • Asahi Pentax Spotmatic II operating manual (PUB. 06461, early).
  • Honeywell Pentax H3v/H1a operating manual.
  • Honeywell Pentax SL operating manual (August 1969).
  • Honeywell Pentax SP 500 operating manual.
  • Honeywell Pentax Spotmatic II operating manual.
  • Honeywell Pentax Spotmatic operating manual (May 1967).
  • Honeywell Pentax Spotmatic operating manual.
  • Asahi Pentax Lenses & Accessories - Complete System of Photography (PUB. 06106).

Manufacturer description #1

Comparatively light and small for its performance, this powerful long-focus lens brings the inaccessible within reach. Its bright f/4.5 image simplifies composition and focusing, and it produces edge-to-edge coverage of high resolution. Equipped with manual diaphragm; supplied with special lenshood.

Smooth helicoidal focusing and a built-on lenshood are two of the features of this highly useful lens. It is praised by news and sports photographers, and has been successfully employed in such diverse applications as accident insurance and criminal investigation work and celestial photography.

Manufacturer description #2

With a focal length 10 times that of a normal lens and a maximum aperture of f4.5, this powerful optic is perfect for all super-telephoto shots, even in poor lighting conditions. Its magnifying power pulls in the most distant objects and there is no more suitable lens for the specialist in search of that extra telephoto effect.

Features

This is a fine super-telephoto lens with a maximum aperture of F4.5. Pentax has succeeded in overcoming the many problems of design that arise with these long lenses: distortion has been practically eliminated, image quality and resolution are high, and the F4.5 brightness is ideal for long·range color photography.

Since the focal length of this lens is 10 times that of a standard lens, it is equipped with a sighting system for ease of operation. A sturdy tripod is necessary as this lens is 44cm long and weighs 3.5kg, but attachment to the camera body is simple since the rear part of the barrel is removable. By loosening the ring, the lens can be twisted through 90° and clicks into position for horizontal or vertical camera position. A lenshood is built in and filters (49mm) can be fitted to the rear of the lens.

Main uses

This lens combines super-telephoto power with brightness, and is therefore ideal for night sports shots, press photography, wild animal studies and many other fields.

Manufacturer description #3

Asahi have overcome all the major problems that arise when undertaking the design and manufacture of a complicated lens of this nature. The result is a sophisticated optical and engineering triumph. Virtually distortion-free with high resolution and excellent colour rendering properties.

Image magnification 10x that of a standard lens, necessitating the very practical inclusion of a sighting system for ease of operation.

A really strong tripod is essential, as the lens measures 44cm overall and weighs 3.5kg.

However, the attachment and removal of the camera body is fast and simple as the rear part of the lens barrel is removable for this purpose. A locking ring permits, when loosened, a 90° rotation of the camera body and clicks positively into the vertical or horizontal position.

The lens features a built-in lens hood and a manually operated click stop diaphragm.

Standard 49mm filters are employed. Good contrast and high resolution even at full working aperture are other important features.

Principal Uses

A specialist lens of telephoto construction. The extreme narrow angle of acceptance (5°) helps one visualise the type of subjects for which this would be employed. A true instance of bringing the inaccessible into reach.

Press photographers find these lenses invaluable for long range celebrity work and there are numerous other uses, including big game in zoo or nature reserve, spo rting events and so on. It is frequently employed for criminal investigation, and celestial photography.

Asahi TAKUMAR series

The first generation of lenses designed for Asahi Pentax 35mm SLR cameras with the M42 screw mount. Introduced with the Asahi Pentax in 1957.

  • Robust, all-metal design with aperture ring(s) and depth-of-field scale in chrome finish (up to 135mm telephotos);
  • Preset or manual diaphragm;
  • Extremely accurate manual focusing with knurled focusing ring (400mm+ super telephotos have finely-ribbed focusing rings);
  • Single-layer anti-reflection coating.

Other super telephoto prime lenses in the Asahi Pentax M42 system

Sorted by focal length and speed, in ascending order
M42 mount (12)
Asahi Tele-Takumar 300mm F/6.3 [363, 43630]P5 - 55.50m⌀58 1965 
Asahi Takumar 300mm F/4M3 - 37.50m⌀82 1958 
Asahi Takumar 300mm F/4 [346, 43460]M4 - 45.50m⌀82 1962 
Asahi Super-Takumar 300mm F/4 [43891, 43894]A5 - 55.50m⌀77 1965 
Asahi Super-Multi-Coated Takumar 300mm F/4 [43892]A5 - 55.50m⌀77 1971 
Asahi Tele-Takumar 400mm F/5.6 [370, 43700]M5 - 58.00m⌀77 1965 
Asahi Super-Multi-Coated Takumar 400mm F/5.6 [43701]M5 - 58.00m⌀77 1971 
Asahi Takumar 500mm F/5 [326, 43260]M2 - 111.00m-- 1957 
Asahi Super-Multi-Coated Takumar 500mm F/4.5 [43661]M4 - 410.00m-- 1971 
Asahi Takumar 1000mm F/8 [334, 43340]M3 - 330.00m-- 1958 
Asahi Tele-Takumar 1000mm F/8 [365, 43650]M5 - 530.00m-- 1965 
Asahi Super-Multi-Coated Takumar 1000mm F/8 [43691]M5 - 530.00m-- 1971 

Lenses with similar focal length

Sorted by manufacturer name
M42 mount (3)
Kuribayashi K.C. Petri Orikkor 500mm F/8P2 - 19.10m-- 1959 
Sigma MF 500mm F/4.5 APO ZENA10 - 85.00m-- 1988 
Carl Zeiss Jena DDR Fernobjektiv 500mm F/8M2 - 16.00mE77 1952 
Interchangeable mount (11)
Century Tele-Athenar 500mm F/5.6 IIM4 - 29.00mS.9 1977 
Century Tele-Athenar 500mm F/4.5 IIM4 - 29.00m
Century Tele-Athenar 500mm F/3.8 IIM4 - 212.00m-- 1977 
Kowa Prominar 500mm F/5.6 FLM7 - 73.00m⌀95 2010 
Meyer-Optik Gorlitz Orestegor 500mm F/5.6P4 - 46.00m⌀118 1965 
Pentacon Prakticar 500mm F/5.6 MCP4 - 46.00m⌀118
Pentacon 500mm F/5.6 [MC]P4 - 46.00m⌀118 1971 
Samyang 500mm F/8 IF MC
aka Bower 500mm F/8 IF MC
aka Opteka 500mm F/8 IF MC
aka Phoenix 500mm F/8 IF MC
aka Rokinon 500mm F/8 IF MC
aka Vivitar Series 1 500mm F/8 IF MC
aka Walimex Pro 500mm F/8 IF MC
P4 - 410.00m⌀67
Samyang 500mm F/8 IF ED MC
aka Rokinon 500mm F/8 IF ED MC
--5 - 410.00m⌀67
Tamron 450mm F/8 [T]
aka Soligor 450mm F/8
P4 - 28.00m⌀67 1963 
Vivitar 500mm F/6.3 [T]P3 - 210.00m--
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Christine L.
Christine L.
6 months ago

Thanks for sharing this information! I have a quick question: do you know how to access the rear filters? I can’t find any information and I’m hoping to use mine for the upcoming solar eclipse. I can’t find an access point on this lens. Any help would be greatly appreciated!

Copyright © 2012-2024 Evgenii Artemov. All rights reserved. Translation and/or reproduction of website materials in any form, including the Internet, is prohibited without the express written permission of the website owner.

Chromatic aberration

There are two kinds of chromatic aberration: longitudinal and lateral. Longitudinal chromatic aberration is a variation in location of the image plane with changes in wave lengths. It produces the image point surrounded by different colors which result in a blurred image in black-and-white pictures. Lateral chromatic aberration is a variation in image size or magnification with wave length. This aberration does not appear at axial image points but toward the surrounding area, proportional to the distance from the center of the image field. Stopping down the lens has only a limited effect on these aberrations.

Spherical aberration

Spherical aberration is caused because the lens is round and the film or image sensor is flat. Light entering the edge of the lens is more severely refracted than light entering the center of the lens. This results in a blurred image, and also causes flare (non-image forming internal reflections). Stopping down the lens minimizes spherical aberration and flare, but introduces diffraction.

Astigmatism

Astigmatism in a lens causes a point in the subject to be reproduced as a line in the image. The effect becomes worse towards the corner of the image. Stopping down the lens has very little effect.

Coma

Coma in a lens causes a circular shape in the subject to be reproduced as an oval shape in the image. Stopping down the lens has almost no effect.

Curvature of field

Curvature of field is the inability of a lens to produce a flat image of a flat subject. The image is formed instead on a curved surface. If the center of the image is in focus, the edges are out of focus and vice versa. Stopping down the lens has a limited effect.

Distortion

Distortion is the inability of a lens to capture lines as straight across the entire image area. Barrel distortion causes straight lines at the edges of the frame to bow toward the center of the image, producing a barrel shape. Pincushion distortion causes straight lines at the edges of the frame to curve in toward the lens axis. Distortion, whether barrel or pincushion type, is caused by differences in magnification; stopping down the lens has no effect at all.

The term "distortion" is also sometimes used instead of the term "aberration". In this case, other types of optical aberrations may also be meant, not necessarily geometric distortion.

Diffraction

Classically, light is thought of as always traveling in straight lines, but in reality, light waves tend to bend around nearby barriers, spreading out in the process. This phenomenon is known as diffraction and occurs when a light wave passes by a corner or through an opening. Diffraction plays a paramount role in limiting the resolving power of any lens.

Doublet

Doublet is a lens design comprised of two elements grouped together. Sometimes the two elements are cemented together, and other times they are separated by an air gap. Examples of this type of lens include achromatic close-up lenses.

Dynamic range

Dynamic range is the maximum range of tones, from darkest shadows to brightest highlights, that can be produced by a device or perceived in an image. Also called tonal range.

Resolving power

Resolving power is the ability of a lens, photographic emulsion or imaging sensor to distinguish fine detail. Resolving power is expressed in terms of lines per millimeter that are distinctly recorded in the final image.

Vignetting

Vignetting is the darkening of the corners of an image relative to the center of the image. There are three types of vignetting: optical, mechanical, and natural vignetting.

Optical vignetting is caused by the physical dimensions of a multi-element lens. Rear elements are shaded by elements in front of them, which reduces the effective lens opening for off-axis incident light. The result is a gradual decrease of the light intensity towards the image periphery. Optical vignetting is sensitive to the aperture and can be completely cured by stopping down the lens. Two or three stops are usually sufficient.

Mechanical vignetting occurs when light beams are partially blocked by external objects such as thick or stacked filters, secondary lenses, and improper lens hoods.

Natural vignetting (also known as natural illumination falloff) is not due to the blocking of light rays. The falloff is approximated by the "cosine fourth" law of illumination falloff. Wide-angle rangefinder designs are particularly prone to natural vignetting. Stopping down the lens cannot cure it.

Flare

Bright shapes or lack of contrast caused when light is scattered by the surface of the lens or reflected off the interior surfaces of the lens barrel. This is most often seen when the lens is pointed toward the sun or another bright light source. Flare can be minimized by using anti-reflection coatings, light baffles, or a lens hood.

Ghosting

Glowing patches of light that appear in a photograph due to lens flare.

Retrofocus design

Design with negative lens group(s) positioned in front of the diaphragm and positive lens group(s) positioned at the rear of the diaphragm. This provides a short focal length with a long back focus or lens-to-film distance, allowing for movement of the reflex mirror in SLR cameras. Sometimes called an inverted telephoto lens.

Anastigmat

A photographic lens completely corrected for the three main optical aberrations: spherical aberration, coma, and astigmatism.

By the mid-20th century, the vast majority of lenses were close to being anastigmatic, so most manufacturers stopped including this characteristic in lens names and/or descriptions and focused on advertising other features (anti-reflection coating, for example).

Rectilinear design

Design that does not introduce significant distortion, especially ultra-wide angle lenses that preserve straight lines and do not curve them (unlike a fisheye lens, for instance).

Focus shift

A change in the position of the plane of optimal focus, generally due to a change in focal length when using a zoom lens, and in some lenses, with a change in aperture.

Transmittance

The amount of light that passes through a lens without being either absorbed by the glass or being reflected by glass/air surfaces.

Modulation Transfer Function (MTF)

When optical designers attempt to compare the performance of optical systems, a commonly used measure is the modulation transfer function (MTF).

The components of MTF are:

The MTF of a lens is a measurement of its ability to transfer contrast at a particular resolution from the object to the image. In other words, MTF is a way to incorporate resolution and contrast into a single specification.

Knowing the MTF curves of each photographic lens and camera sensor within a system allows a designer to make the appropriate selection when optimizing for a particular resolution.

Veiling glare

Lens flare that causes loss of contrast over part or all of the image.

Anti-reflection coating

When light enters or exits an uncoated lens approximately 5% of the light is reflected back at each lens-air boundary due to the difference in refractive index. This reflected light causes flare and ghosting, which results in deterioration of image quality. To counter this, a vapor-deposited coating that reduces light reflection is applied to the lens surface. Early coatings consisted of a single thin film with the correct refractive index differences to cancel out reflections. Multi-layer coatings, introduced in the early 1970s, are made up of several such films.

Benefits of anti-reflection coating:

Circular fisheye

Produces a 180° angle of view in all directions (horizontal, vertical and diagonal).

The image circle of the lens is inscribed in the image frame.

Diagonal (full-frame) fisheye

Covers the entire image frame. For this reason diagonal fisheye lenses are often called full-frame fisheyes.

Extension ring

Extension rings can be used singly or in combination to vary the reproduction ratio of lenses. They are mounted between the camera body and the lens. As a rule, the effect becomes stronger the shorter the focal length of the lens in use, and the longer the focal length of the extension ring.

View camera

A large-format camera with a ground-glass viewfinder at the image plane for viewing and focusing. The photographer must stick his head under a cloth hood in order to see the image projected on the ground glass. Because of their 4x5-inch (or larger) negatives, these cameras can produce extremely high-quality results. View cameras also usually support movements.

135 cartridge-loaded film

43.27 24 36
  • Introduced: 1934
  • Frame size: 36 × 24mm
  • Aspect ratio: 3:2
  • Diagonal: 43.27mm
  • Area: 864mm2
  • Double perforated
  • 8 perforations per frame

120 roll film

71.22 44 56
  • Introduced: 1901
  • Frame size: 56 × 44mm
  • Aspect ratio: 11:14
  • Diagonal: 71.22mm
  • Area: 2464mm2
  • Unperforated

120 roll film

79.2 56 56
  • Introduced: 1901
  • Frame size: 56 × 56mm
  • Aspect ratio: 1:1
  • Diagonal: 79.2mm
  • Area: 3136mm2
  • Unperforated

120 roll film

89.64 56 70
  • Introduced: 1901
  • Frame size: 70 × 56mm
  • Aspect ratio: 5:4
  • Diagonal: 89.64mm
  • Area: 3920mm2
  • Unperforated

220 roll film

71.22 44 56
  • Introduced: 1965
  • Frame size: 56 × 44mm
  • Aspect ratio: 11:14
  • Diagonal: 71.22mm
  • Area: 2464mm2
  • Unperforated
  • Double the length of 120 roll film

220 roll film

79.2 56 56
  • Introduced: 1965
  • Frame size: 56 × 56mm
  • Aspect ratio: 1:1
  • Diagonal: 79.2mm
  • Area: 3136mm2
  • Unperforated
  • Double the length of 120 roll film

220 roll film

89.64 56 70
  • Introduced: 1965
  • Frame size: 70 × 56mm
  • Aspect ratio: 5:4
  • Diagonal: 89.64mm
  • Area: 3920mm2
  • Unperforated
  • Double the length of 120 roll film

Shutter speed ring with "F" setting

The "F" setting disengages the leaf shutter and is set when using only the focal plane shutter in the camera body.

Catch for disengaging cross-coupling

The shutter and diaphragm settings are cross-coupled so that the diaphragm opens to a corresponding degree when faster shutter speeds are selected. The cross-coupling can be disengaged at the press of a catch.

Cross-coupling button

With the cross-coupling button depressed speed/aperture combinations can be altered without changing the Exposure Value setting.

M & X sync

The shutter is fully synchronized for M- and X-settings so that you can work with flash at all shutter speeds.

In M-sync, the shutter closes the flash-firing circuit slightly before it is fully open to catch the flash at maximum intensity. The M-setting is used for Class M flash bulbs.

In X-sync, the flash takes place when the shutter is fully opened. The X-setting is used for electronic flash.

X sync

The shutter is fully synchronized for X-setting so that you can work with flash at all shutter speeds.

In X-sync, the flash takes place when the shutter is fully opened. The X-setting is used for electronic flash.

MF

Sorry, no additional information is available.

Unable to follow the link

You are already on the page dedicated to this lens.

Cannot perform comparison

Cannot compare the lens to itself.

Image stabilizer

A technology used for reducing or even eliminating the effects of camera shake. Gyro sensors inside the lens detect camera shake and pass the data to a microcomputer. Then an image stabilization group of elements controlled by the microcomputer moves inside the lens and compensates camera shake in order to keep the image static on the imaging sensor or film.

The technology allows to increase the shutter speed by several stops and shoot handheld in such lighting conditions and at such focal lengths where without image stabilizer you have to use tripod, decrease the shutter speed and/or increase the ISO setting which can lead to blurry and noisy images.

Original name

Lens name as indicated on the lens barrel (usually on the front ring). With lenses from film era, may vary slightly from batch to batch.

Format

Format refers to the shape and size of film or image sensor.

35mm is the common name of the 36x24mm film format or image sensor format. It has an aspect ratio of 3:2, and a diagonal measurement of approximately 43mm. The name originates with the total width of the 135 film which was the primary medium of the format prior to the invention of the full frame digital SLR. Historically the 35mm format was sometimes called small format to distinguish it from the medium and large formats.

APS-C is an image sensor format approximately equivalent in size to the film negatives of 25.1x16.7mm with an aspect ratio of 3:2.

Medium format is a film format or image sensor format larger than 36x24mm (35mm) but smaller than 4x5in (large format).

Angle of view

Angle of view describes the angular extent of a given scene that is imaged by a camera. It is used interchangeably with the more general term field of view.

As the focal length changes, the angle of view also changes. The shorter the focal length (eg 18mm), the wider the angle of view. Conversely, the longer the focal length (eg 55mm), the smaller the angle of view.

A camera's angle of view depends not only on the lens, but also on the sensor. Imaging sensors are sometimes smaller than 35mm film frame, and this causes the lens to have a narrower angle of view than with 35mm film, by a certain factor for each sensor (called the crop factor).

This website does not use the angles of view provided by lens manufacturers, but calculates them automatically by the following formula: 114.6 * arctan (21.622 / CF * FL),

where:

CF – crop-factor of a sensor,
FL – focal length of a lens.

Mount

A lens mount is an interface — mechanical and often also electrical — between a camera body and a lens.

A lens mount may be a screw-threaded type, a bayonet-type, or a breech-lock type. Modern camera lens mounts are of the bayonet type, because the bayonet mechanism precisely aligns mechanical and electrical features between lens and body, unlike screw-threaded mounts.

Lens mounts of competing manufacturers (Canon, Leica, Nikon, Pentax, Sony etc.) are always incompatible. In addition to the mechanical and electrical interface variations, the flange focal distance (distance from the mechanical rear end surface of the lens mount to the focal plane) is also different.

Lens construction

Lens construction – a specific arrangement of elements and groups that make up the optical design, including type and size of elements, type of used materials etc.

Element - an individual piece of glass which makes up one component of a photographic lens. Photographic lenses are nearly always built up of multiple such elements.

Group – a cemented together pieces of glass which form a single unit or an individual piece of glass. The advantage is that there is no glass-air surfaces between cemented together pieces of glass, which reduces reflections.

Focal length

The focal length is the factor that determines the size of the image reproduced on the focal plane, picture angle which covers the area of the subject to be photographed, depth of field, etc.

Speed

The largest opening or stop at which a lens can be used is referred to as the speed of the lens. The larger the maximum aperture is, the faster the lens is considered to be. Lenses that offer a large maximum aperture are commonly referred to as fast lenses, and lenses with smaller maximum aperture are regarded as slow.

In low-light situations, having a wider maximum aperture means that you can shoot at a faster shutter speed or work at a lower ISO, or both.

Closest focusing distance

The minimum distance from the focal plane (film or sensor) to the subject where the lens is still able to focus.

Closest working distance

The distance from the front edge of the lens to the subject at the maximum magnification.

Magnification ratio

Determines how large the subject will appear in the final image. Magnification is expressed as a ratio. For example, a magnification ratio of 1:1 means that the image of the subject formed on the film or sensor will be the same size as the subject in real life. For this reason, a 1:1 ratio is often called "life-size".

Modified M42 mount

The mount of this lens was modified by the manufacturer to allow exposure metering at full aperture.

Manual diaphragm

The diaphragm must be stopped down manually by rotating the detent aperture ring.

Preset diaphragm

The lens has two rings, one is for pre-setting, while the other is for normal diaphragm adjustment. The first ring must be set at the desired aperture, the second ring then should be fully opened for focusing, and turned back for stop down to the pre-set value.

Semi-automatic diaphragm

The lens features spring mechanism in the diaphragm, triggered by the shutter release, which stops down the diaphragm to the pre-set value. The spring needs to be reset manually after each exposure to re-open diaphragm to its maximum value.

Automatic diaphragm

The camera automatically closes the diaphragm down during the shutter operation. On completion of the exposure, the diaphragm re-opens to its maximum value.

Fixed diaphragm

The aperture setting is fixed at F/4.5 on this lens, and cannot be adjusted.

Number of blades

As a general rule, the more blades that are used to create the aperture opening in the lens, the rounder the out-of-focus highlights will be.

Some lenses are designed with curved diaphragm blades, so the roundness of the aperture comes not from the number of blades, but from their shape. However, the fewer blades the diaphragm has, the more difficult it is to form a circle, regardless of rounded edges.

At maximum aperture, the opening will be circular regardless of the number of blades.

Weight

Excluding case or pouch, caps and other detachable accessories (lens hood, close-up adapter, tripod adapter etc.).

Maximum diameter x Length

Excluding case or pouch, caps and other detachable accessories (lens hood, close-up adapter, tripod adapter etc.).

For lenses with collapsible design, the length is indicated for the working (retracted) state.

Weather sealing

A rubber material which is inserted in between each externally exposed part (manual focus and zoom rings, buttons, switch panels etc.) to ensure it is properly sealed against dust and moisture.

Lenses that accept front mounted filters typically do not have gaskets behind the filter mount. It is recommended to use a filter for complete weather resistance when desired.

Fluorine coating

Helps keep lenses clean by reducing the possibility of dust and dirt adhering to the lens and by facilitating cleaning should the need arise. Applied to the outer surface of the front lens element over multi-coatings.

Filters

Lens filters are accessories that can protect lenses from dirt and damage, enhance colors, minimize glare and reflections, and add creative effects to images.

Lens hood

A lens hood or lens shade is a device used on the end of a lens to block the sun or other light source in order to prevent glare and lens flare. Flare occurs when stray light strikes the front element of a lens and then bounces around within the lens. This stray light often comes from very bright light sources, such as the sun, bright studio lights, or a bright white background.

The geometry of the lens hood can vary from a plain cylindrical or conical section to a more complex shape, sometimes called a petal, tulip, or flower hood. This allows the lens hood to block stray light with the higher portions of the lens hood, while allowing more light into the corners of the image through the lowered portions of the hood.

Lens hoods are more prominent in long focus lenses because they have a smaller viewing angle than that of wide-angle lenses. For wide angle lenses, the length of the hood cannot be as long as those for telephoto lenses, as a longer hood would enter the wider field of view of the lens.

Lens hoods are often designed to fit onto the matching lens facing either forward, for normal use, or backwards, so that the hood may be stored with the lens without occupying much additional space. In addition, lens hoods can offer some degree of physical protection for the lens due to the hood extending farther than the lens itself.

Teleconverters

Teleconverters increase the effective focal length of lenses. They also usually maintain the closest focusing distance of lenses, thus increasing the magnification significantly. A lens combined with a teleconverter is normally smaller, lighter and cheaper than a "direct" telephoto lens of the same focal length and speed.

Teleconverters are a convenient way of enhancing telephoto capability, but it comes at a cost − reduced maximum aperture. Also, since teleconverters magnify every detail in the image, they logically also magnify residual aberrations of the lens.

Lens caps

Scratched lens surfaces can spoil the definition and contrast of even the finest lenses. Lens covers are the best and most inexpensive protection available against dust, moisture and abrasion. Safeguard lens elements - both front and rear - whenever the lens is not in use.